Circular saw blade for cutting ferous materials

ABSTRACT

A saw blade having an annular body ( 12 ) constructed of a first material having a perimeter with a plurality of teeth ( 16 ) formed therein. A plurality of carbide inserts ( 22 ) are affixed to a respective tooth. The carbide inserts include a cutting edge ( 32 ) including a first edge surface ( 40 ) which is generally parallel to an axis of rotation of the blade and a second angled edge surface ( 42 ) which is angled relative to the axis of rotation of the blade and shorter than the first edge surface.

FIELD OF THE INVENTION

The present invention relates generally to circular saw blades, and moreparticularly to circular saw blades including inserts adapted forcutting ferrous material.

BACKGROUND

It is known in the art to have saw blades adapted to cut ferrousmaterial such as steel studs. These saw blades may or may not includeinserts of a hardened material to increase cutting ability. Generally,saw blades that include inserts have carbide tips that are adapted totear-away or chop-away small portions of metal at a time.

Generally, these inserts are formed separately and machined or cutbefore being fit into the saw blade. The machining or forming of theinserts generally includes extensive angles or other shapes being formedinto the insert itself. The different forms of the angles and shapes aregenerally believed to create a greater efficiency in the cutting of amaterial. However, in creating such numerous indentations and angles inthe face or edges of the insert creates additional steps and increasedlabor in the production of the inserts. Furthermore, an inventory ofeach individual insert must be kept on hand for saw blade production.

SUMMARY OF THE INVENTION

The present invention includes a circular saw blade which includes aplurality of teeth situated on the perimeter thereof. Each of theplurality of teeth includes an insert formed of a hardened material,preferably carbide. Each of the inserts includes a leading face whichterminates at a cutting edge at the upper radial edge of the insert. Thecutting edge is defined by an angled surface which includes a shorterside and a longer side. The inserts are arranged such that adjacentinserts have an alternating pattern such that the shorter side of theangled surface is alternated to different sides of the blade.

Further areas of applicability of the present invention will becomeapparent from the detailed description provided hereinafter. It shouldbe understood however that the detailed description and specificexamples, while indicating preferred embodiments of the invention, areintended for purposes of illustration only, since various changes andmodifications within the spirit and scope of the invention will becomeapparent to those skilled in the art from this detailed description.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention will become more fully understood from thedetailed description and the accompanying drawings, wherein:

FIG. 1 is a plan view of a circular saw blade including carbide insertson the teeth according to the principles of the present invention;

FIG. 2 is a detail side view of a saw blade tooth;

FIG. 3A is a front detail of a singular insert according to theprinciples of the present invention; and

FIG. 3B is a top plan view of a single insert according to theprinciples of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to FIGS. 1-3B, a circular saw blade 10 is disclosed. Thecircular saw blade 10 includes a body 12, having two sides 13 a and 13 b(only one side is shown in FIG. 1). The saw blade 10 is designed to turnin the direction of arrow A about an axis of rotation 14. Teeth 16 areformed around the perimeter of the body 12. As best shown in FIG. 2, theteeth 16 each include a shoulder 18 each separated by a gullet 20. Aninsert 22,22′ is affixed to each of the respective shoulders 18. Thegullet 20 is an open area that is formed by an arc 24 where a hip 26 ofa preceding tooth 16 extends over the arc 24 of the gullet 20. The arc24 terminates at the leading face 28 of an insert 22. The leading face28 of the inserts 22,22′ are generally parallel with a radius 30 of thecircular saw blade 10. The radius 30 extends from the axis of rotation14 at the center of the circular saw blade 10. The distal radial edge ofthe inserts 22,22′ include a cutting edge 32,32+ best shown in FIG. 3A,which defines an upper end of the cutting edge of the insert 22.

The inserts 22,22′ are affixed to the tooth 16 through welding,soldering or other suitable means. Thus, the saw blade turns about theaxis of rotation 14 in the direction of arrow A so that the leading face28 of the inserts 22,22′ may engage a material to be cut.

With reference to FIGS. 3A and 3B, the detail of a singular insert 22 isshown. The upper cutting edge of the leading face 28 of the insert 20includes a cutting edge 32. The insert 22 further includes two sides 34,36 and a base 38 extending between the sides 34, 36. The cutting edge ofthe leading face 28 has a width of approximately 1.75 mm with each ofthe sides 34, 36 tapering inward approximately 0.09 mm at the base end38. The cutting edge 32 is created by two edge surfaces 40, 42 whichterminate into respective sides 34, 36 of the insert 22. The first edgesurface 40 is generally perpendicular to the axis of rotation 14 of theblade 10. The second angled edge surface 42 is ground at approximately a10-30° angle “x”, preferably approximately 20° across approximately onethird of the tooth width thus forming angled surface 42. The first andsecond edge surfaces 40,42 interface along line 43, as best shown inFIG. 3A. The inserts 22′, have a leading face 28 which is a mirror imageof the leading face 28 of the inserts 22 and are placed on alternatingteeth around the periphery of the saw blade 10. In other words, theangled second edge surface 42 of the cutting edges 32,32′ of inserts22,22′ respectively are disposed on alternate sides 13 a,13 b of theblade along the circumference of the circular saw blade 10.

As the circular saw blade 10 rotates about the axis of rotation 14 eachalternating cutting edge 32, 32′ takes material from a different side ofthe channel being cut.

Preferably, the insert 20 is formed of a carbide material including,preferably, 8.6% TiC, 12% Ta(Nb)C, and 9.5% Co. Furthermore, the averagepreferred grain size of the carbide material would be in the range of1-1.5 micrometers in diameter.

The cutting edges 32,32′ of the inserts 22,22′ preferably have a backangle “y” of between 5° and 15° and preferably 10°, as illustrated inFIG. 2. The back angle of the inserts 22,22′ leads into a curved upper(or peripheral) surface 44 of the teeth 16. The curved upper surface 44terminates into the hip 26 which provides a rounded surfacetransitioning into the arc 24 of the gullet. According to a preferredembodiment, the hip 26 is spaced a distance d from a tangent line ofadjacent cutting edge tips 32,32′ of approximately 0.5 mm.

The invention being thus described, it will be obvious that the same maybe varied in many ways. Such variations are not to be regarded as adeparture from the spirit and scope of the invention, and all suchmodifications as would be obvious to one skilled in the art are intendedto be included within the scope of the following claims.

1. A circular saw blade, comprising: an annular body constructed of afirst material having a perimeter with a plurality of shoulders formedinto said perimeter; and a plurality of inserts each affixed to arespective one of said shoulders, said inserts formed of a secondmaterial and including a cutting edge defined along a leading face, eachsaid cutting edge including a first edge surface generally parallel toan axis of rotation of the annular body and including a second anglededge surface between 10° and 30° offset from parallel to an axis ofrotation of the annular body.
 2. The saw blade according to claim 1,wherein said cutting edge of said inserts include an interface betweensaid first edge surface and said second angled edge surface which iscloser to a side of said annular body wherein the interface of adjacentinserts are closer to alternate sides of the annular body.
 3. The sawblade according to claim 1, wherein said inserts are formed fromcarbide.
 4. The saw blade according to claim 3, wherein said carbideinserts include approximately 8.6 percent TiC, 12 percent TaNbc, and 9.5percent Co.
 5. The saw blade according to claim 1, wherein said cuttingedge of said inserts include a back angle of between 5° and 15°.
 6. Thesaw blade according to claim 5, wherein said back angle is approximately10°.
 7. An insert for a saw blade comprising: a body portion defining aleading face having a cutting edge, a first and second side, and abottom edge, said cutting edge defined by a first edge surface extendinggenerally perpendicular from said first side and a second angled edgesurface intersecting said first angled surface and extending between100° and 120° from said second side.
 8. The insert according to claim 7,wherein said body portion is made from carbide.
 9. The insert accordingto claim 8, wherein said body portion includes approximately 8.6 percentTiC, 12 percent TaNbC, and 9.5 percent Co.
 10. The insert according toclaim 7, wherein said cutting edge includes a back angle of between 5°and 15°.
 11. The insert according to claim 10, wherein said back angleis approximately 10°.
 12. The insert according to claim 7, wherein saidsecond angled edge surface extends at approximately 110° from saidsecond side.